Expansion tensioner



FIG. 1 is a bottom perspective view of an expansion tensioner showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a bottom view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 is a top perspective view thereof. 

CLAIM The ornamental design for an expansion tensioner, as shown and described. 